In the new awards contender “Her,” now open in theaters, Scarlett Johansson plays a computer operating system named Samantha. Her performance has critics buzzing: The Post’s film editor Lou Lumenick called Johansson’s performance “a vocal tour de force.” And even though the Golden Globes deemed her ineligible for a nomination, an Oscar nod is still a possibility.

But she’s not the first actor to capture our hearts without even appearing on-screen. Here are eight other non-animated voice-over performances you need to check out.

Kevin Spacey as GERTY in “Moon”

Allan Lane as Mister Ed on “Mister Ed”

Cowboy Allan “Rocky” Lane went uncredited for his mastery as the voice of everyone’s favorite talking horse. But his work set the tone for many a talking animal to come.

Ron Howard as the narrator on “Arrested Development”

It’s impossible to imagine the magic of the cult hit comedy without that distinctive voice leading us through the crazy scenarios.

Douglas Rain as HAL 9000 in “2001: A Space Odyssey”

Rain’s performance as the villainous computer HAL 9000 made a strong case for eliminating computers all together. There are few things creepier than his line, “Dave, this conversation can serve no purpose anymore. Goodbye.”

Daniel Stern as the narrator on “The Wonder Years”

Photo: Everett Collection

As the narrator on the beloved drama series, Stern voices Kevin Arnold 20 years in the future. His performance was the show’s adult spirit.

Nick Bakay as Salem on “Sabrina, the Teenage Witch”

Sabrina couldn’t have gotten through high school if it weren’t for her wisecracking cat, Salem. And we wouldn’t have stood for a talking a black cat if he hadn’t been so darn funny.

Paul Bettany as J.A.R.V.I.S. in the “Iron Man” movies

Behind every super hero is a Just a Rather Very Intelligent System, a k a J.A.R.V.I.S., the computer with a British accent. Where would Tony Stark be without him taking care of everything around the house?

Jim Henson as Kermit on “The Muppet Show”

Photo: Everett Collection

One of the most iconic voices of all time, Henson’s charisma as the little green guy captured the hearts of kids and parents alike.